Condensate trap for heating-cooling systems

ABSTRACT

A condensation trap comprising an inlet chamber, a vent chamber and an outlet chamber. The inlet chamber is configured to receive condensate fluid through an external opening therein. The vent chamber is in fluid communication with the inlet chamber via a first passageway that includes an internal opening of the inlet chamber. The internal opening is located substantially at an opposite end of the vent chamber as the external opening. The outlet chamber is in fluid communication with the vent chamber via a second passageway that includes an internal opening in a sidewall of the vent chamber and an interior opening in an end of the outlet chamber. The outlet chamber is configured to transmit the condensate fluid through an exterior opening located at an opposite end of the outlet chamber. A vent volume portion is greater than a total volume of an internal space of the inlet chamber.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser.No. 61/295,501, filed by Shailesh S. Manohar, et al., on Jan. 15, 2010,entitled, “An Improved Heating Furnace for a HVAC System”, andincorporated herein by reference in its entirety.

TECHNICAL FIELD

This application is directed, in general, to heating-cooling systems,and more specifically, to removing condensation from such systems.

BACKGROUND

Heating-cooling systems, such as heating, ventilating and airconditioning (HVAC) systems often include a furnace and heat exchangerto heat the air circulated by the system. As air flows through thesystem, condensation can form. Water condensate can potentially causethe malfunction of, or damage to, components of the system, andtherefore it is desirable to remove condensate from the system.Typically, a condensate box and trap are provided to facilitate thedraining of condensation fluids from furnace components through whichproducts of combustion are exhausted from the furnace, such as headerboxes and exhaust vents.

In some systems, an increase in furnace vent lengths means the trap hasto operate under conditions where the atmospheric pressure on the trapundergoes large changes when a furnace transitions between a neutral or“off” state to an operating or “on” state. Additionally, some furnacecondensate traps designs can have two or more input connection pointsand can have a large internal volume. Such design features tend toincrease the minimum size of the trap, which in turn, undesirablyreduces installation flexibility.

SUMMARY

One embodiment of the present disclosure is a condensation trapcomprising an inlet chamber, a vent chamber and an outlet chamber. Theinlet chamber is configured to receive condensate fluid through anexternal opening therein. The vent chamber is in fluid communicationwith the inlet chamber via a first passageway that includes an internalopening of the inlet chamber. The internal opening is locatedsubstantially at an opposite end of the vent chamber as the externalopening. The outlet chamber is in fluid communication with the ventchamber via a second passageway that includes an internal opening in asidewall of the vent chamber and an interior opening in an end of theoutlet chamber. The outlet chamber is configured to transmit thecondensate fluid through an exterior opening located at an opposite endof the outlet chamber. A vent volume portion, which includes an internalspace of the vent chamber that is below the exterior opening, is greaterthan a total volume of an internal space of the inlet chamber.

Another embodiment of the present disclosure is a condensationmanagement system. The system comprises a condensation collection boxconfigured to collect condensate fluid. The system also comprises atransfer hose having one end coupled to the condensation collection boxand the above-described a condensation trap. The inlet chamberconfigured to receive the condensate fluid through an external openingcoupled an opposite end of the transfer hose.

Another embodiment of the present disclosure is a method ofmanufacturing the above-described condensation trap. The methodcomprises providing a mold, the mold defining an enclosed cavity thatincludes spaces to accommodate, the inlet chamber, the vent chamber, andthe outlet chamber as described above. The method also comprisesintroducing a moldable material into the mold, allowing the allowing themoldable material to solidify to a casting, and removing the castingfrom the mold to provide the condensation trap.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is now made to the following descriptions taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 presents a cross-sectional view of an example embodiment of acondensation trap of the disclosure;

FIGS. 2A and 2B presents a cross-sectional views of other exampleembodiments of a condensation trap of the disclosure;

FIG. 3 presents a perspective view of an example condensation trap ofthe disclosure analogous to that depicted in FIG. 2A or 2B;

FIG. 4A-4C presents a cross-sectional view of selected features of acondensation management system of the disclosure which includes anexample condensation trap of the disclosure depicted in differentoperational states of the system;

FIG. 5 presents a flow diagram of an example method of manufacturing acondensation trap of the disclosure, such as any of the example trapsdepicted in FIGS. 1-4C.

DETAILED DESCRIPTION

One embodiment of the present disclosure is a condensation trap. Onefeature of the disclosed trap is an internal vent volume portion that islarger than an inlet chamber internal volume. As further discussed belowsuch a feature facilitates the trap's ability to accommodate certaininlet pressures without causing the trap to lose its prime, while alsofacilitating a compact trap design.

FIG. 1 presents a cross-sectional view of an example embodiment of acondensation trap 100 of the disclosure. FIGS. 2A and 2B presentcross-sectional views of other example embodiments of a condensationtrap 100 of the disclosure.

Turning to FIG. 1, the trap 100 comprises an inlet chamber 102configured to receive condensate fluid (not shown) through an externalopening 104 therein. The trap 100 also comprises a vent chamber 106 influid communication with the inlet chamber 102 via a first passageway108. The first passageway 108 includes an internal opening 110 of theinlet chamber 102. The internal opening 110 is located substantially atan opposite end 112 of the inlet chamber 102 at an end 114 of thechamber 105 where the external opening 104 is located. The trap 100further comprises an outlet chamber 116 in fluid communication with thevent chamber 106 via a second passageway 118 that includes an internalopening 120 in a sidewall 122 of the vent chamber 106 and also includesan interior opening 124 at an end 126 of the outlet chamber 116. Theoutlet chamber 116 is configured to transmit the condensate fluidthrough an exterior opening 128 at an opposite end 130 of the outletchamber 116. A vent volume portion of the trap 100, which includes aninternal space 132 of the vent chamber 106 that is below the exterioropening 128 (e.g., below a high fluid mark 134 for the embodiment inFIG. 1 after which fluid accumulation get transmitted into the outletchamber 116), is greater than a total volume of an internal space 136 ofthe inlet chamber 102.

The term fluid communication, as used herein, means that a fluid in theinternal space of one chamber can be transmitted via a passageway toanother communicating chamber. E.g., a condensate fluid in inlet chamber102 can flow into the vent chamber 106 via the pathway 108. E.g., acondensate fluid in the vent chamber 106 can flow into the outletchamber 116 via the pathway 118.

In some embodiments of the trap 100, such as shown in FIG. 1, tofacilitate a compact trap design, a major dimension 138 of the inletchamber 102 and a major dimension 140 of the vent chamber 106 aresubstantially parallel to each other. E.g., in some cases, thedimensions 138, 140 forms a divergent angle of about 0±20 degrees. Asfurther illustrated, in some embodiments, to facilitate the drainage ofcondensate fluid out of the outlet chamber (e.g., gravity drainage), amajor dimension 142 of the outlet chamber 116 is substantiallyperpendicular to the major dimension 140 of the vent chamber 106. E.g.,in some cases the major dimensions 140, 142 forms a divergent angle ofabout 90±20 degrees.

As further illustrated in FIG. 1, in some embodiments, when thecondensation trap 100 is positioned in a condensation management system405 (e.g., FIG. 4A), to facilitate the capture and retention ofcondensate fluid, the major dimension 138 of the inlet chamber 102 andthe major dimension 140 of the vent chamber 106 are substantiallyvertically oriented. And, to facilitate draining the condensate fluid,the major dimension 142 of the outlet chamber 128 is substantiallyhorizontally oriented. E.g., inlet chamber 102 and vent chamber 106 themajor dimensions 138, 140 are substantially perpendicular (e.g., formingan incident angle of 90±20 degree) with respect to a floor or mountingbase 410 that supports a furnace 415 that the condensation managementsystem 405 is part of (FIG. 4A). E.g., the outlet chamber 116 majordimension 142 is substantially parallel (e.g., forming an incident angleof 0±20 degree) with respect to the floor or base.

As also illustrated in FIG. 1, in some embodiments, when thecondensation trap 100 is positioned in a condensation management system405 (FIG. 4A), to facilitate fluid drainage, the inlet chamber externalopening 104 is vertical raised above the outlet chamber exterior opening128. The difference in height 144 between the inlet chamber externalopening 104 is vertical raised above the outlet chamber exterior opening128 would depend upon an number of factors including the ranges ofpressures at the inlet opening 104, the ratio of the vent volume portionto the total volume of the inlet chamber internal space 136. Forinstance, in some embodiments when the ratio of the vent volume portionto the total volume is in a range of about 4:1 to 5:1. The difference inheight 144 can be about 5 inches.

Such features are conducive to providing a compact trap design that isable to drain condensate fluid to the exterior opening 128 of the outletchamber 116 against a negative pressure at the external opening 104 ofthe inlet chamber 102. E.g., in some embodiments there can be a negativepressure at the external opening 104 that corresponds to a −5 inchcolumn of water at standard conditions of 20° C. and 1 atmosphere ofpressure. E.g., in some embodiments, a major dimension length 146 of thetrap 100 is about 7 inches or less.

As also depicted in FIG. 1, the vent chamber 106 is in communicationwith the ambient atmosphere via an exterior vent opening 148 of the ventchamber 106. In some embodiments, a cross-sectional area of the exteriorvent opening 148 in the vent chamber 106 is greater than across-sectional area of the inlet chamber external opening 104. In someembodiments, such a configuration is conducive to providing a ventvolume portion (e.g., internal space 132) of the vent chamber 106 thatis greater than the total volume of the input chamber 102 (e.g.,internal space 136) as discussed above and to reducing the overallheight 146 of the trap 100 and thereby facilitate the trap 100 readilyfitting into the small confines of a heating-cooling system (e.g., afurnace housing). Such can be the case, for instance, when the sidewalls 122 of the vent chamber 106 and the side walls 150 of the inputchamber 102 are straight walls. In such embodiments, the cross-sectionalareas of the exterior opening 148 and inlet chamber external opening 104can be geometrically related to the vent volume portion of the ventchamber 106 and the total volume of the input chamber 102, respectively.For instance, in some embodiments the ratio of the cross-sectional areasof the exterior vent opening 148 to the inlet chamber external opening104 equals about 2:1.

As further depicted in FIG. 1, in some cases, the inlet chamber 102 andthe vent chamber 106 are in direct fluid communication via the firstpassageway 108 which further includes an interior opening 150 in thevent chamber 106 that is substantially concentric with the internalopening 110 in the inlet chamber 102.

As also illustrated in FIG. 1, in some embodiments, the vent chamber 106can further include another exterior opening 152 on an opposite end 154of the vent chamber 106 as the end 156 where the exterior vent opening148 is located. The exterior opening 152 is configured to hold removableplug 158 therein. The exterior opening 152 can serve as a clean-outport, e.g., to facilitate periodic cleaning of the inside of the traps100 of debris which may build-up in the trap 100 and block the flow ofcondensate fluid there through. In some cases, the plug 158 can includea freeze preventer device 160. In other cases, however, the freezepreventer device 160 can be installed in the trap independently of theplug 158. Embodiments of the freeze preventer device 160 can include oneor more resistive heating elements 162 configured to apply heat (e.g.,via an electrical current applied to the elements 162 via leads 164)when the inside of the trap 100 is exposed to near-freezingtemperatures, such as the case when the trap 100 is installed in anunconditioned space. A built-in freeze preventer device 160 to preventfreezing can advantageously avoid the need to wrap electric heating tapearound the trap 100 to prevent freezing.

As illustrated in FIGS. 2A and 2B, in some embodiments, the wherein saidfluid communication from said inlet chamber 102 to the vent chamber 106further includes an intermediate chamber 210 located between the inletchamber 102 and the vent chamber 106. An internal space 215 of theintermediate chamber 210 located below the outlet exterior opening 116is part of the vent volume portion. For example, the vent volume portionincludes the internal space 132 of the vent chamber 106 and internalspace 215 of the intermediate chamber 210 that is below the exterioropening 120 (e.g., below the high fluid mark 134).

In some cases, the inclusion of the intermediate chamber 210 facilitatesthe manufacture of the condensation trap 100, e.g., by simplifying aninjection molding process used to form the interconnected chambers 102,106, 116, 210 and can allow the use or standard tubing sizes tofacilitate attaching the trap to other components of a condensationmanagement system.

As further illustrated in FIG. 2A, in some embodiments of the trap 100,the intermediate chamber 210 can include an interior opening 220 that issubstantially concentric with the inlet chamber internal opening 110,and, an interior sidewall 225 opening 230 that is substantiallyconcentric with an interior opening in sidewall 150 of the vent chamber106. In some cases, the inlet chamber internal opening 110 and interiorsidewall 225 opening 230 can also be concentric with the outlet interioropening 124. However, in some embodiments such as illustrated in FIG.2B, there may be substantially no sidewalls that separate the ventchamber 106 from the intermediate chamber 210. For the example, theinterior opening in sidewall 150 of the vent chamber 106 and theinterior sidewall 225 opening 230 of the intermediate chamber 210 caninclude substantially all of portions of these two chambers 106, 210that overlap in the trap 100

As further illustrated in FIGS. 2A and 2B, in some embodiments, theintermediate chamber 210 further includes an external opening 235 on anopposite side of the trap 100 as the inlet chamber external opening 104.In certain embodiments, an intermediate chamber 210 external opening 235can be configured to hold a removable plug 158 or freeze preventerdevice 160, similar to (or in addition to) that described for theexterior opening 152 of the vent chamber 106 in the context of FIG. 1.

FIG. 3 presents a perspective view of an example condensation trap 100of the disclosure that is analogous to that depicted in FIG. 2A or 2B.As illustrated, in some embodiments of the trap 100, one or more of theinlet chamber 102, the vent chamber 106, the outlet chamber 116, oroptional intermediate chamber 210, can be substantiallycylindrically-shaped. For instance, in some embodiments, thecylindrically-shaped chambers 102, 106, 116, 210 can correspond tostandardized sizes of tubing (e.g., polyvinyl chloride, PVC, tubinghaving a ¾ inch outer diameter and ½ inch inner diameter) commonly usedin the heating-cooling industry facilitate coupling to other componentsof a condensation management system.

As further illustrated in FIG. 3 embodiments of the trap 100 can be aunitary body, such that walls 305 of the chambers 102, 106, 116, 210 arecomposed of a same material (e.g., PVC) formed in a single-stepinjection molding process. In some cases, the trap 100 can furtherinclude one or more mounting bodies 310 to facilitate attachment of thetrap 100 to other components of a condensation management system, orother components of a heating cooling system. In some embodiments, themounting bodies 310 are part of the same unitary body the chamber wallsare composed of.

Another embodiment of the present disclosure is condensation managementsystem that comprises the condensation trap disclosed herein. FIG. 4A-4Cpresents a cross-sectional view of selected features of a condensationmanagement system 405 of the disclosure which includes an examplecondensation trap 100 of the disclosure. The example trap 100 isdepicted in different operational states of the system 400 in each ofFIGS. 4A, 4B and 4C. In some embodiments, the condensation managementsystem 405 is incorporated into a component of a heating-cooling system400 such as a furnace 415.

As illustrated, the condensation management system 405 comprises acondensation collection box 420 configured to collect condensate fluid425. For instance, condensate fluid 425 collected in one or more fluespipe 430 of the furnace 415 can be coupled to the collection box 420 viaone or more flue hoses 435.

The system 405 also comprises a transfer hose 440 having one end 442coupled to the condensation collection box 420 and another end 444coupled to the trap 100. The condensation trap 100 comprises the inletchamber 102, vent chamber 106, and outlet chamber 116 such as describedabove, and can further include other features such as discussed above inthe context of FIGS. 1-3. The other end 444 of the transfer hose 430 iscoupled to the inlet exterior opening 104 of the trap 100 (FIG. 1).

In some preferred embodiments, the trap 100 is optimized for use in anegative-pressure only condensation management system 405. That is, whenin operation, the condensation collection box 420 is configured togenerate only a negative pressure, which in turn, causes a negativepressure (relative to the ambient atmospheric pressure) at the exterioropening 104 coupled to the box 420. When not in operation, the pressureof the condensation collection box 420 and at the exterior opening 104is neutral (relative to the ambient atmospheric pressure). This is incontrast to some condensation management systems which are configured todeal both vent draining and condensation collection box draining thatgenerate a positive and negative pressure at its condensation collectionbox at different stages of operation.

For instance, FIG. 4A shows the condensation management system 405 whenit is not in operation and the pressure in the condensation collectionbox 420 and at the exterior opening 104 is substantially neutral. Insuch a state, the condensate fluid 425 levels in the trap 100 aresubstantially the same in the inlet chamber 102 and the vent chamber106. FIG. 4B shows the condensation management system 405 when in aninitial stage of operation. The condensation collection box 420generates a negative pressure, and, the corresponding negative pressureat the exterior opening 104 of the inlet chamber 102, causes condensatefluid 425 in the trap 100 to move from the vent chamber 106 to the inletchamber 102. However, due to the vent volume portion being larger thanthe inlet chamber's 102 internal total volume the vent chamber 106 isnot fully depleted of condensate fluid 425 during this operationalstate. Based on the present disclosure one of ordinary skill in the artwould understand how to adjust the relative sizes of the vent volumeportion and inlet internal total volume to accommodate various negativepressures at the exterior opening 104. FIG. 4C shows the condensationmanagement system 405 when in a latter stage of operation. As condensatefluid 425 accumulates in the system 405 the condensate fluid 425 drainsfrom the condensation collection box 420 to the trap 100 and out of theoutlet chamber 116.

Another embodiment of the present disclosure is a method ofmanufacturing a condensation trap. FIG. 5 presents a flow diagram of anexample method 500 of manufacturing a condensation trap of thedisclosure, such as any of the embodiments of the traps 100 discussed inthe context of FIGS. 1-4C, certain components of which are referred tothroughout below.

The method 500 comprises a step 510 of providing a mold that defines anenclosed cavity that defines the trap structure. The enclosed cavityincludes the inlet chamber 102, vent chamber 106 and outlet chamber 116configured as described above in the context of FIGS. 1-4C. One ofordinary skill in the art would understand how to fabricate such molds,e.g., by machining and including internal inserts as needed to definethe chambers 102, 106, 116 and other structures of the trap 100.

The method 500 further comprises a step 520 of introducing a moldablematerial into the mold. In some embodiments for instance a moldablematerial comprising a polymer powder (e.g., PVC power or PVC powderalloyed with other polymers or plasticizers) can be heated and mixed toa homogenous flowable state and then introduced into the mold inaccordance with step 520 by transferring the moldable material into theenclosed cavity. In some preferred embodiments, the introduction step520 can further include a single-step injection-mold process 525. Thesingle-step injection molding process (step 525) can provide substantialtime and cost savings as compared to alternative processes where, e.g.,individual parts of the trap are individually molded and then glued orfitted together.

The method 500 further comprises a step 530 of allowing the moldablematerial to solidify into a casting, and, a step 540 of removing thecasting from the mold to provide the condensation trap.

Those skilled in the art to which this application relates willappreciate that other and further additions, deletions, substitutionsand modifications may be made to the described embodiments.

What is claimed is:
 1. A condensation trap, comprising: an inlet chamberconfigured to receive condensate fluid through an external openingtherein; a vent chamber in fluid communication with said inlet chambervia a first passageway that includes an internal opening of said inletchamber, said internal opening located substantially at an opposite endof said vent chamber as said external opening; and an outlet chamber influid communication with said vent chamber via a second passageway thatincludes an internal opening in a sidewall of said vent chamber and aninterior opening in an end of said outlet chamber, said outlet chamberconfigured to transmit said condensate fluid through an exterior openinglocated at an opposite end of said outlet chamber; an intermediatechamber located between said inlet chamber and said vent chamber,wherein an internal space of said intermediate chamber located belowsaid exterior opening is part of said vent volume portion, wherein saidfluid communication from said inlet chamber to said vent chamberincludes said intermediate chamber, and wherein a vent volume portion ofsaid vent chamber that is below said exterior opening and that isdefined by a portion of a side wall of said vent chamber, is greaterthan a total volume of an internal space of said inlet chamber, whereinsaid portion of said side wall of said vent chamber extends from saidexterior opening to said opposite end of said vent chamber in adirection that is parallel to a direction of a major dimension of saidvent chamber, and wherein said condensation trap is configured to drainsaid condensate fluid to said exterior opening of said outlet chamberagainst a negative pressure generated in a condensation collection boxcoupled to said external opening of said inlet chamber.
 2. Thecondensation trap of claim 1, wherein a major dimension of said inletchamber and a major dimension of said vent chamber are substantiallyparallel with each other and a major dimension of said outlet chamber issubstantially perpendicular to said major dimension of said ventchamber.
 3. The condensation trap of claim 1, wherein, when saidcondensation trap is positioned in a condensation management system,said major dimension of said inlet chamber and said major dimension ofsaid vent chamber are substantially vertically oriented and said majordimension of said outlet chamber is substantially horizontally oriented.4. The condensation trap of claim 1, wherein, when said condensationtrap is positioned in a condensation management system said inletchamber external opening is vertical raised above said outlet chamberexterior opening.
 5. The condensation trap of claim 1, wherein a ratioof said vent volume portion to said total volume of said inlet chamberis in a range of about 4:1 to about 5:1.
 6. The condensation trap ofclaim 1, wherein a major dimension length of said trap is less thanabout 7 inches.
 7. The condensation trap of claim 1, wherein across-sectional area of an exterior opening in said vent chamber isgreater than a cross-sectional area of said inlet chamber externalopening.
 8. The condensation trap of claim 1, wherein said inlet chamberand said vent chamber are in direct fluid communication via said firstpassageway which further includes an interior opening in said ventchamber that is substantially concentric with said internal opening insaid inlet chamber.
 9. The condensation trap of claim 1, wherein saidintermediate chamber includes: an interior opening that is substantiallyconcentric with said inlet chamber internal opening, and an interiorsidewall opening that is substantially concentric with said interioropening of said vent chamber.
 10. The condensation trap of claim 1,wherein said intermediate chamber further includes an external openingon an opposite side of said trap as said inlet chamber external opening.11. The condensation trap of claim 10, wherein said intermediate chamberexternal opening is configured to hold a removable plug.
 12. Thecondensation trap of claim 11, wherein said plug includes a freezepreventer device.
 13. The condensation trap of claim 1, wherein one ormore of said inlet chamber, said outlet chamber and said vent chamberare substantially cylindrically-shaped.
 14. The condensation trap ofclaim 1, wherein said side wall of said vent chamber and a side wall ofsaid input chamber are both straight walls and are both parallel to saiddirection of said major dimension of said vent chamber.
 15. Thecondensation trap of claim 1, wherein said total volume of said internalspace of said inlet chamber is defined by said sidewall of said wall ofsaid input chamber extending from said from said external opening ofsaid inlet chamber to said internal opening of said inlet chamber.